The file that stores macro-enabled slide shows and presentations. PPSM stores a set of slides with graphics, audio and video information, which cannot be edited. It’s used solely to view the generated presentations. To run PPSX file macros, you should first save the file with the PPSM extension.
A file to store presentations with tables, drawings, texts, audio and video created using open source programs: OpenOffice, StarOffice, LibreOffice, etc. The file is editable and based on the XML format. Is an open alternative to the closed PPT format.